KIN 358 Exam 2

RER

Acronym for the ratio of carbon dioxide expired to oxygen consumed at the level of the lungs.

lactate threshold

The point during exercise of increasing intensity at which blood lactate begins to accumulate above resting levels, where lactate clearance is no longer able to keep up with lactate production. (two words)

BMR

Acronym for the lowest rate of body metabolism (energy use) that can sustain life.

direct calorimetry

A method that gauges the body's rate and quantity of energy production (calorimetry) by measuring the body's heat production. (two words)

maximal oxygen uptake

The maximal capacity for oxygen consumption by the body during maximal exertion. It is also known as aerobic power, maximal oxygen intake, maximal oxygen consumption, and cardiorespiratory endurance capacity. (three words)

fatigue

General sensations of tiredness and accompanying decrements in muscular performance

RMR

The body's metabolic rate early in the morning following an overnight fast and 8 hours of sleep.

calorimeter

A device for measuring the heat produced by the body (or by specific chemical reactions).

Haldane transformation

An equation allowing one to calculate the inspired air volume from expired air volume, or expired air volume from inspired air volume. (two words)

EPOC

Acronym for elevated oxygen consumption above resting levels after exercise; at one time referred to as oxygen debt.

indirect calorimetry

A method of estimating energy expenditure (calorimetry) by measuring respiratory gases. (two words)

VO2 drift

A slow increase in VO2 during prolonged submaximal exercise at a constant power output. (two words)

calorie

A unit of measure for energy and heat.

In events lasting longer than a few seconds, glycogen stored in the _________ is the primary energy source for ATP synthesis.

a. liver b. heart c. pancreas d. muscle

d. muscle

Sprints in running, cycling, and swimming do not result in accumulation of lactic acid.

a. true b. false

b. false

What factor does NOT affect total daily caloric expenditure?

a. age b. sex c. size d. height

d. height

If maximal adaptation to VO2max is achieved in 8 to 12 weeks of training, yet endurance performance continues to improve, which is most likely the cause for the continued improvement?

a. reductions in mitochondrial mass b. increase in the number of slow-twitch muscle fibers c. increased RMR d. increased lactate threshold

d. increased lactate threshold

Lactic acid may actually have beneficial effects on exercise performance, contrary to what most exercisers think.

a. true b. false

a. true

A high lactate threshold indicates ___________________.

a. very good endurance capabilities b. a high consumption of fat c. a high rate of protein metabolism d. greater muscular strength

a. very good endurance capabilities

Fatigue is different from muscle weakness or damage, because it is reversible with rest.

a. true b. false

a. true

Most researchers now prefer to use the term resting metabolic rate (RMR) instead of basal metabolic rate (BMR), because RMR is an easier measurement to take than BMR.

a. true b. false

a. true

When muscles appear to be nearly exhausted, playing music will not help increase the strength of muscle contraction.

a. true b. false

b. false

Direct calorimetry is widely regarded as a useful tool for exercise measurements.

a. true b. false

b. false

The role of the CNS in most types of fatigue is to limit exercise performance ____________.

a. based on metabolic exhaustion b. as a protective mechanism c. based on perceptions of fatigue d. all of the above

b. as a protective mechanism

Most studies have reported that glycogen is spared when carbohydrate is ingested during prolonged, strenuous exercise.

a. true b. false

b. false

arteries

Blood vessels that transport blood away from the heart.

stroke volume

The amount of blood ejected from the left ventricle during contraction; the difference between the end-diastolic volume and the end-systolic volume. (two words)

mechanoreceptor

An end organ that responds to changes in mechanical stress, such as stretch, compression, or distension.

baroreceptor

Stretch receptor located within the cardiovascular system that senses changes in blood pressure.

venules

Small vessels that transport blood from the capillaries to the veins and then back to the heart.

bradycardia

A resting heart rate lower than 60 beats/min.

vasodilation

The dilation of blood vessels.

arterioles

The smallest arteries that transport blood from larger arteries to the capillaries.

hematocrit

The percentage of cells or formed elements in the total blood volume; more than 99% of cells or formed elements made up of red blood cells.

Purkinje fibers

The fibers that make up the terminal branches of the AV bundle and that transmit impulses through the ventricles six times faster than through the rest of the cardiac conduction system.

hemoglobin

The iron-containing pigment in red blood cells that binds oxygen.

veins

Blood vessels that transport blood back to the heart.

hematopoiesis

Increased red blood cell concentration by increased production of cells.

myocardium

The muscle of the heart.

pericardium

A double-layered outer covering of the heart.

electrocardiograph

A machine used to obtain an electrocardiogram.

tachycardia

A resting heart rate greater than 100 beats/min.

capillaries

The smallest vessels transporting blood from the heart to the tissues and the actual sites of exchange between the blood and tissue.

What statement about the left ventricle is true?

a. The mechanisms for its adaptation and performance with disease are the same as those observed with aerobic training. b. It needs to generate only minimal force to pump blood to the cardiac system. c. Many sudden deaths among young athletes are due to left ventricular atrophy. d. It will hypertrophy in response to both aerobic training and resistance training.

d. It will hypertrophy in response to both aerobic training and resistance training.

What statement is true?

a. The heart is about the size of your fist and is located on the left side of the thoracic cavity. b. The superior and inferior vena cava return blood from the body to the left atria. c. The function of the cavity between the pericardium and the heart is to hold fluid that reduces friction between the sac and the beating heart. d. The two ventricles act as receiving chambers and the two atria act as sending chambers.

c. The function of the cavity between the pericardium and the heart is to hold fluid that reduces friction between the sac and the beating heart

Low resting heart rate in endurance athletes is uncommon and could be an indication of pathological bradycardia.

a. true b. false

b. false

During exercise, in addition to transporting oxygen and nutrients to active muscles and regulating temperature, blood also helps to

a. lower mean arterial pressure b. maintain the proper body pH c. minimize swelling of active areas d. regulate heart rate

b. maintain the proper body pH

Symptoms of both bradycardia and tachycardia include fatigue, dizziness, lightheadedness, and fainting.

a. true b. false

a. true

What is an example of external control of heart activity?

a. The SA node initiates the impulse. b. The impulse enters the AV bundle, then travels along the ventricular septum and branches into both ventricles. c. Norepinephrine and epinephrine both increase heart rate. d. The Purkinje fibers transmit the impulse extremely quickly through the ventricles, causing all parts of the ventricle to contract at about the same time.

c. Norepinephrine and epinephrine both increase heart rate.

In order for blood to flow in a vessel there must be a pressure difference from one end of the vessel to the other end of the vessel. Blood will flow from the region of the vessel with low pressure to the region of the vessel with high pressure.

a. true b. false

b. false; it will flow from high to low

What situation is optimal for physical performance?

a. a low hematocrit with an accompanying low plasma volume b. a low hematocrit with a decreased number of red blood cells c. a low hematocrit with a normal or slightly elevated number of red blood cells d. a high hematocrit with a very low plasma volume

c. a low hematocrit with a normal or slightly elevated number of red blood cells

The relaxation phase in one full cardiac cycle is called

a. diastole b. systole

a. diastole

The contraction phase in one full cardiac cycle is called

a. diastole b. systole

b. systole

The diastolic phase is longer than the systolic phase.

a. true b. false

a. true

The reason that there is a pressure differential from the arterial to the venous circulation is that the blood vessels themselves provide resistance or impedance to blood flow. The resistance that the vessel provides is largely dictated by the properties of the blood vessels and the blood itself.

a. true b. false

a. true

What is NOT a role the sympathetic nervous system plays in regulating the distribution of blood?

a. It causes muscle cells to contract, constricting vessels so that less blood can pass through. b. Under normal conditions, it transmits impulses continuously to blood vessels, keeping the vessels in a state of moderate constriction to maintain adequate blood pressure. c. During a crisis and during exercise, it causes vasodilation directly through sympathetic fibers that supply some blood vessels in skeletal muscles and in the heart, increasing blood flow to the muscles and the heart. d. It sends CO2, K+, and oxygen to body tissues in response to the arteriole's autoregulatory mechanisms.

d. It sends CO2, K+, and oxygen to body tissues in response to the arteriole's autoregulatory mechanisms.

How does myocardium differ from skeletal muscle?

a. Cardiac muscle fibers are not interconnected like skeletal muscle is. b. Myocardial fibers are mosaic rather than homogenous. c. Myocardium contains mainly type II fibers. d. Cardiac muscle contraction occurs by "calcium-induced calcium release."

d. Cardiac muscle contraction occurs by "calcium-induced calcium release."

The active contraction of the atria that completes the process of blood moving passively from the atria to the ventricles is sometimes called a

a. shove b. kick c. push d. jump start

b. kick

What statement is true?

a. EPO increases hematocrit without affecting blood viscosity. b. Athletes generally have a higher hematocrit than their sedentary counterparts. c. Hematocrit is generally higher in women than in men because of the estrogen effect. d. Redistribution of blood can result from local dilators, the vessel endothelium, and pressure changes.

d. Redistribution of blood can result from local dilators, the vessel endothelium, and pressure changes.

Henry's law

The law stating that gases dissolve in liquids in proportion to their partial pressures, depending also on their solubilities in the specific fluids and on the temperature. (two words)

internal respiration

The exchange of gases between the blood and tissues. (two words)

respiratory centers

Autonomic centers located in the medulla oblongata and the pons that establish breathing rate and depth. (two words)

myoglobin

A compound similar to hemoglobin, but found in muscle tissue, that carries oxygen from the cell membrane to the mitochondria.

external respiration

The process of bringing air into the lungs and the resulting exchange of gas between the alveoli and the capillary blood. (two words)

respiratory membrane

The membrane separating alveolar air and blood, composed of the alveolar wall, the capillary wall, and their basement membranes. (two words)

alveoli

Terminal air sac at the end of the bronchial tree in the lungs, where gas exchange takes place with the capillaries.

respiratory pump

Passive movement of blood through the central circulation as a function of pressure changes during breathing. (two words)

pulmonary ventilation

The movement of gases into and out of the lungs. (two words)

expiration

The process by which air is forced out of the lungs through relaxation of the inspiratory muscles and elastic recoil of the lung tissue, which increases the pressure in the thorax.

Boyle's gas law

Law stating that at a constant temperature, the number of gas molecules in a given volume depends on the pressure. (three words)

partial

The pressure exerted by an individual gas in a mixture of gases.

Fick's law

Law stating that the net diffusion rate of a gas across a fluid membrane is proportional to the difference in partial pressure, proportional to the area of the membrane, and inversely proportional to the thickness of the membrane. (two words)

pulmonary diffusion

The exchange of gases between the lungs and the blood. (two words)

inspiration

The active process involving the diaphragm and the external intercostal muscles that expands the thoracic dimensions and thus the lungs; the expansion decreases pressure in the lungs, allowing outside air to rush in.

An increased PCO2 stimulates the inspiratory center to increase respiration to

a. bring in more oxygen b. rid the body of excess CO2 and minimize pH changes c. increase the oxygen diffusion capacity d. stabilize the arterial-venous oxygen difference

b. rid the body of excess CO2 and minimize pH changes

As the rate of oxygen use decreases, the arterial-venous oxygen difference increases.

a. true b. false

b. false

The increase in oxygen diffusion capacity from rest to exercise in healthy individuals is caused by

a. the highly developed diffusion capacity of the bottom third of the lung b. increased blood flow through the lungs c. limited perfusion of the upper regions of the lungs because of gravity d. a relatively inefficient circulation of blood through the lungs at rest

b. increased blood flow through the lungs

The arterial-venous oxygen difference reflects an increased extraction of oxygen from venous blood by active muscle, thus decreasing the oxygen content of the arterial blood.

a. true b. false

b. false

Gases move from an area of low partial pressure to an area of high partial pressure.

a. true b. false

b. false

As an athlete exercises, ________________.

a. the ability to unload oxygen to the muscles decreases as the muscle pH decreases b. CO2 concentration decreases because of increased metabolism c. the contact time of blood and the alveolar air increases d. blood temperature rises slightly, causing hemoglobin to unload oxygen more efficiently

d. blood temperature rises slightly, causing hemoglobin to unload oxygen more efficiently

Oxygen diffusion capacity increases as a person moves from rest to exercise.

a. true b. false

a. true

When carbon dioxide is released from the cells, it is carried in the blood in all of these forms EXCEPT

a. bound to hemoglobin b. dissolved in plasma c. carbonic acid d. as bicarbonate ions

c. carbonic acid

When the lungs' stretch receptors sense an excessive stretch, that information is relayed to the expiratory center, which responds by shortening the duration of an inspiration, thereby decreasing the risk of over-inflating the respiratory structures. This is known as the _______________.

a. overinflation reflex action b. Hering-Breuer reflex c. pulmonary stretch reactor d. Bohr effect

b. Hering-Breuer reflex

The goal of respiration is to ____________________.

a. help slow heart activity b. decrease ventilation so that less chemical stimulation occurs c. maintain appropriate levels of blood and tissue gases and maintain proper pH for normal cellular function d. reduce the rate of metabolism

c. maintain appropriate levels of blood and tissue gases and maintain proper pH for normal cellular function

The blood's oxygen-carrying capacity is a limiting factor of performance in healthy people.

a. true b. false

b. false

Which statement is true?

a. Hemoglobin and myoglobin are very different in structure. b. Hemoglobin has a much greater affinity for oxygen than myoglobin. c. Myoglobin delivers oxygen to the mitochondria. d. The myoglobin dissociation curve tends to be flatter than the hemoglobin dissociation curve.

c. Myoglobin delivers oxygen to the mitochondria.

The pneumotaxic center regulates inspiratory volume by _____________.

a. prolonging the firing of the inspiratory neurons b. inhibiting inspiration c. exciting the inspiratory neurons

b. inhibiting inspiration

Chemoreceptors in the aortic arch are less sensitive to changes in H+ concentrations and PCO2 than are the carotid chemoreceptors.

a. true b. false

a. true

afterload

Resistance to blood being ejected from the left ventricle.

hemoconcentration

A relative (not absolute) increase in the cellular content per unit of blood volume, resulting from a reduction in plasma volume.

maximum heart rate

The highest heart rate value attainable during an all-out effort to the point of exhaustion. (HRmax) (three words)

total peripheral resistance

The resistance to the flow of blood through the entire systemic circulation. (TPR) (three words)

Valsalva maneuver

The process of holding the breath and attempting to compress the contents of the abdominal and thoracic cavities, causing increased intra-abdominal and intrathoracic pressure. (two words)

exercise-induced arterial hypoxemia

A decline in arterial PO2 and arterial oxygen saturation during maximal or near-maximal exercise. (four words)

resting heart rate

The heart rate at rest, averaging 60 to 80 beats/min. (RHR) (three words)

preload

The degree to which the myocardium is stretched before it contracts, determined by factors such as central blood volume.

Frank-Starling mechanism

The mechanism by which an increased amount of blood in the ventricle causes a stronger ventricular contraction to increase the amount of blood ejected. (three words)

hyperventilation

A breathing rate or tidal volume greater than necessary for normal function.

cardiovascular drift

An increase in heart rate during exercise to compensate for a decrease in stroke volume. (two words)

central command

Information originating in the brain that is transmitted to the cardiovascular, muscular, or pulmonary systems. (two words)